Objective: To investigate the treatment outcome of laparoscopic partial nephrectomy in the patients with renal tumors of moderate to high complexity (R.E.N.A.L. score 7-10). Methods: In the study, 186 patients with a renal score of 7-10 renal tumors who underwent laparoscopic partial nephrectomy in Peking University Third Hospital from February 2016 to April 2021 were selected. Laparoscopic partial nephrectomy was performed after examination. The patients were followed-up, and their postoperative hemoglobin, creatinine, complications, and length of hospital stay recorded. The data were represented by mean±standard deviation or median (range). Results: There were 128 males and 58 females in this group, aged (54.6±12.8) years, with body mass index of (25.4 ± 3.4) kg/m²; The tumors were located in 95 cases on the left and 91 cases on the right, with maximum diameter of (3.1±1.2) cm. The patient's preoperative hemoglobin was (142.9±15.8) g/L, and blood creatinine was 78 μmol/L (47-149 μmol/L). According to preoperative CT images, the R.E.N.A.L. score was 7 points for 43 cases, 8 points for 67 cases, 9 points for 53 cases, and 10 points for 23 cases. All the ope-rations were successfully completed, with 12 cases converted to open surgery. The operation time was 150 minutes (69-403 minutes), the warm ischemic time was 25 minutes (3-60 minutes), and the blood loss was 30 mL (5-1 500 mL). There were 9 cases of blood transfusions, with a transfusion volume of 800 mL (200-1 200 mL). Postoperative hemoglobin was (126.2±17.0) g/L. The preoperative crea-tinine was 78 μmol/L (47-149 μmol/L), the postoperative creatinine was 83.5 μmol/L (35-236 μmol/L), the hospital stay was 6 days (3-26 days), and surgical results achieved "the trifecta" in 87 cases (46.8%). In the study, 167 cases were followed up for 12 months (1-62 months), including 1 case with recurrence and metastasis, 4 cases with metastasis, and 2 cases with other tumors (1 case died). Conclusion: Laparoscopic partial nephrectomy is safe and effective in the treatment of renal tumors with R.E.N.A.L. score of 7-10. Based on the complexity of the tumor, with the increase of difficulty, the warm ischemia time and operation time tend to increase gradually, while "the trifecta" rate gradually decreases. The complications of this operation are less, and the purpose of preserving renal function to the greatest extent is achieved.